Power Tool Including an Internal Auxiliary Power Supply

This application claims the benefit of U.S. Provisional Patent Application No. 63/706,910, filed Oct. 14, 2024, and the entire content of which is hereby incorporated by reference.

Embodiments described herein relate to battery pack powered power tools.

Electric power tools receive power from a power source to drive a load. Some electric power tools are corded to receive power from an external power source, such as a power outlet positioned in a wall. Other electric power tools receive power from a battery pack.

Battery-powered power tools allow for increased portability and convenience by eliminating the need for the electric cord anchored to the external power source.

Power tools described herein include a power tool housing, an interface configured to receive a battery pack, an internal energy storage circuit located within the power tool housing, a trigger for user control of power tool operation, a plurality of switches configured to connect the battery pack and the internal energy storage circuit in series or parallel, and a controller. The controller is configured to receive a control signal from the trigger, control the power tool based on the control signal, control the plurality of switches to set a power source configuration of the power tool by selectively connecting the battery pack, the internal energy storage circuit, or both the battery pack and the internal energy storage circuit to a load of the power tool, and provide energy to the load of the power tool according to the power source configuration.

Electrical devices described herein include an internal energy storage circuit, a plurality of switches configured to connect a battery pack and the internal energy storage circuit in series or parallel, and a controller. The controller is configured to control the plurality of switches to set a power source configuration of a power tool by selectively connecting the battery pack, the internal energy storage circuit, or both the battery pack and the internal energy storage circuit to a load of the power tool. The controller is configured to provide energy to the load of the power tool according to the power source configuration.

Methods of providing auxiliary power to a battery pack powered power tool based on operation parameters of the power tool described herein include controlling, via a controller of the power tool, a plurality of switches to connect a battery pack and an internal energy storage circuit of a power tool in series or parallel. The methods also include controlling, via the controller, the plurality of switches to set a power source configuration of the power tool by selectively connecting the battery pack, the internal energy storage circuit, or both the battery pack and the internal energy storage circuit to a load of the power tool, and providing, via the power source configuration, energy to the load of the power tool.

Before any embodiments are explained in detail, it is to be understood that the embodiments are not limited in application to the details of the configurations and arrangements of components set forth in the following description or illustrated in the accompanying drawings. The embodiments are capable of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings.

Unless the context of their usage unambiguously indicates otherwise, the articles “a,” “an,” and “the” should not be interpreted as meaning “one” or “only one. ” Rather these articles should be interpreted as meaning “at least one” or “one or more. ” Likewise, when the terms “the” or “said” are used to refer to a noun previously introduced by the indefinite article “a” or “an,” “the” and “said” mean “at least one” or “one or more” unless the usage unambiguously indicates otherwise.

In addition, it should be understood that embodiments may include hardware, software, and electronic components or modules that, for purposes of discussion, may be illustrated and described as if the majority of the components were implemented solely in hardware. However, one of ordinary skill in the art, and based on a reading of this detailed description, would recognize that, in at least one embodiment, the electronic-based aspects may be implemented in software (e.g., stored on non-transitory computer-readable medium) executable by one or more processing units, such as a microprocessor and/or application specific integrated circuits (“ASICs”). As such, it should be noted that a plurality of hardware and software based devices, as well as a plurality of different structural components, may be utilized to implement the embodiments. For example, “servers,” “computing devices,” “controllers,” “processors,” etc., described in the specification can include one or more processing units, one or more computer-readable medium modules, one or more input/output interfaces, and various connections (e.g., a system bus) connecting the components.

Relative terminology, such as, for example, “about,” “approximately,” “substantially,” etc., used in connection with a quantity or condition would be understood by those of ordinary skill to be inclusive of the stated value and has the meaning dictated by the context (e.g., the term includes at least the degree of error associated with the measurement accuracy, tolerances [e.g., manufacturing, assembly, use, etc.] associated with the particular value, etc.). Such terminology should also be considered as disclosing the range defined by the absolute values of the two endpoints. For example, the expression “from about 2 to about 4” also discloses the range “from 2 to 4”. The relative terminology may refer to plus or minus a percentage (e.g., 1%, 5%, 10%) of an indicated value.

It should be understood that although certain drawings illustrate hardware and software located within particular devices, these depictions are for illustrative purposes only.

Functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. In some embodiments, the illustrated components may be combined or divided into separate software, firmware and/or hardware. For example, instead of being located within and performed by a single electronic processor, logic and processing may be distributed among multiple electronic processors. Regardless of how they are combined or divided, hardware and software components may be located on the same computing device or may be distributed among different computing devices connected by one or more networks or other suitable communication links. Similarly, a component described as performing particular functionality may also perform additional functionality not described herein. For example, a device or structure that is “configured” in a certain way is configured in at least that way but may also be configured in ways that are not explicitly listed.

Accordingly, in the claims, if an apparatus, method, or system is claimed, for example, as including a controller, control unit, electronic processor, computing device, logic element, module, memory module, communication channel or network, or other element configured in a certain manner, for example, to perform multiple functions, the claim or claim element should be interpreted as meaning one or more of such elements where any one of the one or more elements is configured as claimed, for example, to make any one or more of the recited multiple functions, such that the one or more elements, as a set, perform the multiple functions collectively.

Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

Some electric power tools receive power from a battery pack to drive a load. Battery pack powered power tools allow for increased portability and convenience by eliminating the need for an electric cord. However, in high-power-demand applications, users often face different experiences when using different battery packs. Low-power packs may not be able to deliver enough current to complete a demanding application for a high-power tool (e.g., circular saws, chainsaws, etc.). Low current delivery can lead to slower application time, tool bogging during application, or overheating battery packs (for example, due to the high demand on the pack). Using a high-power battery pack in demanding applications can lead to terminal overheating, power electronics overheating, and/or motor overheating. User experience may be improved by an additional, in-tool energy storage device (e.g., a battery cell, a capacitor, etc., located within a housing of the tool) that can be controlled in different ways to overcome the issues described above by providing auxiliary power to a power tool motor in various applications, in addition to power provided by a battery pack.

Embodiments described herein relate to an internal energy storage circuit for a power tool that is selectively controlled to provide auxiliary power to the power tool. The auxiliary power may be used to supplement power provided by a battery pack or may be used as the sole source of power for the power tool. Thus, in some embodiments, the internal energy storage circuit enables the power tool to continue to operate when executing tasks that require more power than otherwise available from battery pack cells alone. Further, in some embodiments, the internal energy storage circuit selectively provides power to the motor, which supplements power provided by the battery pack, thereby reducing the power burden on the battery pack. In other embodiments, the internal energy circuit alone is used to provide power to the power tool motor, such as when a battery pack of the power tool is hot swapped during operation, or when attaching the battery pack would make the power tool too unwieldy for the task to be performed.

1 FIG. 100 100 100 105 110 115 120 125 125 120 125 105 100 illustrates an example of a battery pack powered power toolincluding an internal energy storage circuit. In this example, the power toolis a hammer drill-driver and may be referred to as a hammer drill. The power toolincludes a tool housing, a handle, a trigger, a base, and a battery pack. In some embodiments, the battery packmay be a rechargeable battery pack including a battery pack housing that is removably coupled to the base. The battery pack housing houses a plurality of battery cells and a battery controller configured to control the charging and discharging of the battery cells (e.g., via power switching elements). The plurality of battery cells may be lithium ion (“Li-ion”) cells, Nickel-Cadmium (“Ni-Cad”) cells, or cells of another chemistry type. Collectively, the cells may provide nominal output voltages of different values, including but not limited to 4V, 12V, 18V, 28V, 36V, 40V, 80V, 120V, etc. In other embodiments, the battery packmay be integrated within the housingof the power tool.

100 125 130 135 135 135 140 105 100 140 140 140 The power toolreceives power from the battery packand drives an output shafthaving a tool bit receiver(e.g., a chuck). The tool bit receiveris configured to receive a driver bit that drives a screw into a work material, a drill bit that drills a hole into a work material, or another tool bit. In various embodiments, different types of tool bits may be inserted into the tool bit receiverdepending on properties of the work material and the desired task. A mode selectoris positioned on the housingand allows a user to select a desired operation mode of the power tool(e.g., drill, hammer drill, or drive at a particular clutch setting). In the present embodiment, the mode selectoris configured as a ring selector that allows the user to rotationally select the desired operation mode. In other embodiments, the mode selectormay be configured to select operating modes or applications for the internal energy storage circuit. In some embodiments, the mode selectormay be another type of user interface, such as a user interface having buttons, switches, or electronic displays such as touchscreens.

100 100 Although, the example power toolis shown as a hammer drill, the power toolmay be any motorized power tool that is battery pack powered and that drives an output shaft (e.g., chuck, saw blade holder, or arbor). Such power tools include, for example, impact wrenches, impact drivers, nailers, reciprocating saws, circular saws, table saws, cutters, drill-drivers, hammers, grinders, and the like.

2 FIG. 200 100 200 100 200 245 270 250 272 274 212 140 255 260 280 shows a controllerfor the power tool. The controlleris electrically and/or communicatively connected to a variety of modules or components of the power tool. For example, the illustrated controlleris connected to indicators, current sensor(s), speed sensor(s), temperature sensor(s), secondary sensor(s)(e.g., a voltage sensor, an accelerometer, a torque sensor or torque transducer, etc.), the user interface(e.g., mode selector), a power switching network, a power input unit, and a motor.

200 200 100 200 205 222 220 225 205 210 215 218 205 222 220 225 200 242 The controllerincludes a plurality of electrical and electronic components that provide power, operational control, and protection to the components and modules within the controllerand/or power tool. For example, the controllerincludes, among other things, a processing unit(e.g., a microprocessor, an electronic processor, an electronic controller, a microcontroller, or another suitable programmable device), a memory, input units, and output units. The processing unitincludes, among other things, a control unit, an arithmetic logic unit (“ALU”), and a plurality of registersand is implemented using a known computer architecture (e.g., a modified Harvard architecture, a von Neumann architecture, etc.). The processing unit, the memory, the input units, and the output units, as well as the various modules connected to the controllerare connected by one or more control and/or data buses (e.g., common bus). The use of one or more control and/or data buses for the interconnection between and communication among the various modules and components would be known to a person skilled in the art in view of the embodiments described herein.

222 205 222 222 222 100 222 200 200 222 200 The memoryis a non-transitory computer readable medium and includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as a ROM, a RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, a hard disk, an SD card, or other suitable magnetic, optical, physical, or electronic memory devices. The processing unitis connected to the memoryand executes software instructions that are capable of being stored in a RAM of the memory(e.g., during execution), a ROM of the memory(e.g., on a generally permanent basis), or another non-transitory computer readable medium such as another memory or a disc. Software included in the implementation of the power toolcan be stored in the memoryof the controller. The software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The controlleris configured to retrieve from the memoryand execute, among other things, instructions related to the control processes and methods described herein. In other embodiments, the controllerincludes additional, fewer, or different components.

200 280 212 115 280 212 290 125 280 200 255 280 255 200 280 255 280 200 280 280 280 280 280 250 The controllerdrives the motorto rotate an output (e.g., a driver) in response to a user's manipulation of the user interface(e.g., depressing trigger). The output may be coupled to the motorvia an output shaft. Manipulation of the user interfacemay cause power to be drawn from battery pack(e.g., battery pack), to drive the motorat a specific speed and in a specific direction. In some embodiments, the controllercontrols the power switching network(e.g., a FET switching bridge) to drive the motor. The power switching networkmay include, for example, a plurality of high side switching elements (e.g., FETs) and a plurality of low side switching elements (e.g., FETs). The controllermay control each switch of the plurality of high side switching elements and the plurality of low side switching elements to drive each phase of the motor. For example, the power switching networkmay be controlled to more quickly decelerate the motor. In some embodiments, the controllermonitors a rotation of the motor(e.g., a rotational rate of the motor, a velocity of the motor, a position of the motor, a rotational direction of the motor, and the like) via the speed sensors.

245 200 200 100 245 245 100 245 100 245 100 245 The indicatorsare also connected to the controllerand receive control signals from the controllerto turn on and off or otherwise convey information based on different states of the power tool. The indicatorsinclude, for example, one or more light-emitting diodes (“LEDs”) and/or a display screen (e.g., an electronic display). The indicatorscan be configured to display conditions of, or information associated with, the power tool. For example, the indicatorscan display information relating to an operational state of the power tool, such as a mode or speed setting. The indicatorsmay also display information relating to a fault condition, or other abnormality of the power tool. In addition to or in place of visual indicators, the indicatorsmay also include a speaker or a tactile feedback mechanism to convey information to a user through audible or tactile outputs.

285 200 290 285 100 290 285 260 255 290 260 255 260 285 200 260 200 100 292 290 280 100 292 280 100 280 100 292 292 A battery pack interfaceis connected to the controllerand is configured to couple with battery pack. The battery pack interfaceincludes a combination of mechanical (e.g., a battery pack receiving portion) and electrical components configured to and operable for interfacing (e.g., mechanically, electrically, and communicatively connecting) the power toolwith the battery packs. The battery pack interfaceis coupled to the power input unitand the switching network, and transmits the power received from the battery packto the power input unitand the switching network. The power input unitmay also include active and/or passive components (e.g., voltage step-down controllers, voltage converters, inverters, rectifiers, filters, etc.) to regulate or control the power received through the battery pack interfaceand to the controller. The power input unitmay also include switches configured to be controlled by the controllerto set a power source configuration of the power toolby placing the internal energy storage circuitin series or parallel with the battery packand a load (e.g., motoror other components of the power tool), or to connect or disconnect the internal energy storage circuitto the motoror other components of the power toolas required to provide appropriate power to the motorand other components of the power toolin accordance with the embodiments described below. Although the internal energy storage circuitis often described herein as an electric device (e.g., a supercapacitor, battery cell(s), etc.), it is contemplated that the internal energy storage circuitmay be a mechanical or chemical energy storage device such as a flywheel, a mechanical spring, a pneumatic piston, a heat battery, etc.

270 290 292 280 270 280 270 250 280 250 272 255 290 292 280 The current sensor(s)sense, for example, a current provided by the battery pack, a current provided by the internal energy storage circuit, a current associated with the motor, or a combination thereof. In some embodiments, the current sensor(s)sense at least one of the phase currents of the motor. The current sensormay be, for example, an inline phase current sensor, a pulse-width-modulation-center-sampled inverter bus current sensor, or the like. The speed sensorssense a speed of the motor. The speed sensormay include, for example, one or more Hall effect sensors. In some embodiments, the temperature sensorsenses a temperature of the switching network, the battery pack, the internal energy storage circuit, the motor, or a combination thereof.

212 115 140 140 115 212 200 212 In the embodiment shown, the user interfaceincludes the triggerand the mode selectorand generates control signals in response to a user selection of an operation mode via the mode selectorand/or depressing the trigger. In some embodiments, a trigger depression sensor also serves as at least part of the user interfaceand provides a control signal to the controller. The trigger depression sensor may be, for example, a potentiometer providing a varying signal (e.g., between 0-5 volts) proportionally representing the amount of trigger depression. In some embodiments, the user interfacemay include other controlled user inputs, such as a forward/reverse selector, which generate responsive control signals, such as indicating a shifting of the forward/reverse selector, and are not exhaustively detailed herein.

212 200 255 290 280 255 290 280 280 280 250 270 272 274 200 280 292 280 The control signals from the user interfaceare transmitted to the controller, which activates the switching networkto draw power from the battery packand drive the motor. By selectively enabling and disabling the switching network, power from the battery packis selectively applied to stator windings of the motorto cause rotation of a rotor of the motor. The rotating rotor of the motordrives the output shaft. The sensors,,,provide motor information feedback (e.g., motor current information, motor rotational position information, motor rotational velocity information, motor temperature, etc.), which can be used by the controllerto drive the motorand, as described in further detail below, determine whether the internal energy storage circuitshould be activated to provide additional power to the motor.

200 100 290 280 292 105 100 212 245 105 100 292 105 100 115 212 105 The controllerand other components of the power toolare also electrically coupled to and receive power from the battery pack. In the embodiment shown, the motorand internal energy storage circuitare included (e.g., located) within the housingof the power tool, while only a portion of the user interfaceand the other components (e.g., indicators) are visible external to the housingof the power tool. The internal energy storage circuitis, for example, embedded into an interior wall of the housing(e.g., in the handle of the power tool) while the trigger (e.g., trigger) of the user interfaceis accessible at the exterior of the housing.

125 125 100 125 18 100 100 100 100 In the embodiment shown, the battery packincludes a single battery pack. However, in some embodiments, a plurality of battery packsmay be connected to the power toolto provide power. For example, in some embodiments, two or more separate battery packsof the same voltage (e.g., twoV battery packs) may be connected to the power toolto provide power to the power tool. As another example, in some embodiments, two or more separate battery packs of different voltages (e.g., a 12V battery pack and an 18V battery pack) may be connected to the power toolto provide power to the power tool.

2 FIG. 295 290 290 295 292 290 292 292 295 290 292 295 292 125 Also shown inis a battery chargerthat is coupleable to the battery packto charge the battery cells of the battery pack. In some embodiments, the battery chargermay also be coupleable to the internal energy storage circuitvia the battery packto charge the internal energy storage circuit. For example, an electronic processor and memory included in the battery pack may execute instructions to selectively enable current to flow to the internal energy storage circuitfrom the chargervia the battery pack. In some embodiments, the internal energy storage circuitis within the charger, and the internal energy storage circuitenables increased charging speed of the battery pack.

3 FIG. 392 390 100 380 100 390 100 100 200 390 392 392 200 392 295 100 100 shows a first application of an internal energy storage circuit. In the embodiment shown, a battery packis connected to the power tool, but the motorof the power toolis not being operated. In response to the battery packbeing connected to the power tool, the power tool(e.g., controller) enables current flow from the connected battery packto the internal energy storage circuitto charge the internal energy storage circuit. The controllermay also be configured to enable charging of the internal energy storage circuit(via the charger) between operations of the power tool(e.g., when the power toolis idling or not being operated at all).

4 FIG. 492 100 492 480 100 480 250 270 272 274 245 200 100 492 200 492 490 200 492 490 492 492 490 492 492 480 212 280 115 480 492 492 490 shows a second application of an internal energy storage circuit. In the embodiment shown, the power tooldraws energy from the internal energy storage circuitto drive the motorof the power tooland other components (e.g., the motor, the sensors,,,, the indicators, etc.). For example, the controllermay be configured to determine that driving a component of the power tool(e.g., a light of the power tool) could be accomplished via power drawn only from the internal energy storage circuit. In such a case, the controllermay connect only the internal energy storage circuit(and not the battery pack) to the component to provide the required power. In the embodiment shown, the controllermay charge the internal energy storage circuitbetween periods of use using power drawn from the battery pack. Further, if the internal energy storage circuitis fully charged or the efficient operation of the power tool requires it, the internal energy storage circuitmay be used to charge the battery pack. According to this application, the internal energy storage circuitcan be used for high-power-demand operations without placing any load on the battery pack. In some embodiments, the internal energy storage circuitmay also be configured to be charged via regenerative braking of the motor. Specifically, in response to the user interfacebeing manipulated to cease operation of the motor(e.g., when the user releases the trigger), the momentum of the motorcan be used to generate current to charge the internal energy storage circuitwith regenerative braking. Similarly, the internal energy storage circuitcan be used to charge the battery pack.

5 FIG. 592 592 580 100 590 200 100 590 592 250 270 272 274 200 130 100 200 590 592 590 580 592 shows a third application of an internal energy storage circuit. In the embodiment shown, the internal energy storage circuithas been depleted, for example, during operation of the motor(e.g., according to the second application described above) and the power toolcontinues to operate from power from the battery pack. The controllermay be configured to determine whether operation of the power toolrequires a high level of power and, based on the determination, prevent the battery packfrom providing power to charge the internal energy storage circuit. For example, if the sensors (e.g., sensors,,,) communicate a signal to the controllerindicating that the output shaftof the power toolis experiencing an amount of reverse torque exceeding a predetermined level (e.g., above 1000 foot pounds of torque), the controllermay, in response to the signal, prevent the battery packfrom charging the internal energy storage circuitand instead allocate all current drawn from the battery packto driving the motor. As previously described, the internal energy storage circuitcan also be recharged using regenerative braking.

6 FIG. 692 200 690 692 692 200 250 270 272 274 690 690 200 692 690 680 690 692 692 680 692 100 690 692 690 shows a fourth application of an internal energy storage circuit. The controlleris configured to connect the battery packand internal energy storage circuitin parallel, and to draw power from the internal energy storage circuitto complete the task that requires a high power (e.g., high torque). In the embodiment shown, the controllermay be configured to detect (e.g., via sensors,,,) a demand (e.g., such as voltage demand or a current demand) on the battery packabove a predefined threshold. In response to detecting the increased demand on the battery pack, the controllermay connect the internal energy storage circuitin parallel with the battery packto provide additional power to the motorsuch that the demand on the battery packfalls below the pre-determined threshold. With this fourth application of the internal energy storage circuit, it is possible to complete short-time, high-power-demand tasks (e.g., finishing a cut through a tough material) in boost mode in which both the internal energy storage circuitand the battery back 625 provide power to the motorsimultaneously in parallel. When the internal energy storage circuitis depleted, the power toolcan run as normal from the battery pack. As previously described, the internal energy storage circuitcan also be recharged using regenerative braking or during a down time with energy from the battery pack.

7 FIG. 792 200 792 792 780 200 250 270 272 274 200 100 790 200 280 792 790 792 790 shows a fifth application of an internal energy storage circuit. In the embodiment shown, the motor controlleris configured to draw power only from the internal energy storage circuitat the start of a task requiring a high starting motor current or power (in comparison to the motor current or power required for maintaining the motor speed during the performance of the task after startup). Specifically, in the embodiment shown, the internal energy storage circuitalone may be used primarily for initially spinning up the motorof the power tool (e.g., for starting a task, such as mixing, having a high initial torque requirement). The controllermay be configured to determine, based on signals from the sensors,,,, that a predetermined operation speed is achieved. In response to determining that the predetermined operation speed is achieved, the controllermay cause the power toolto be operated solely from the battery pack. In some embodiments, the controllermay spin up the motorusing both the internal energy storage circuitand the battery pack. As previously described, the internal energy storage circuitcan also be recharged using regenerative braking or during a down time with energy from the battery pack.

8 FIG. 892 200 280 892 890 100 891 100 890 891 892 890 890 891 100 200 250 270 272 274 890 100 880 890 100 200 880 892 891 100 200 880 880 891 892 890 891 892 shows a sixth application of an internal energy storage circuit. In the embodiment shown, the controlleris configured to drive the motorusing energy only from internal energy storage circuitfor a period during which a primary battery packhas been detached from the power tooland before a secondary battery packis attached to the power tool. Accordingly, hot swapping of the battery packs (,) is enabled by use of the internal energy storage circuit. For example, a part of a task may be completed by using power drawn from battery pack, then, as the battery packs,are swapped, the power toolmay continue operating on power drawn from the internal energy storage circuit. In the embodiment shown, controlleris configured to determine (e.g., based on signals from sensors,,,) that the primary battery packwas detached from the power toolduring operation of the motor. In response to detecting that battery packwas disconnected from the power tool, the controllerdrives the motorusing power provided by the internal energy storage circuit. In response to the second battery packbeing connected to the power tool, the controllercontinues operation of the motorby driving the motorwith power drawn from the secondary battery pack. As previously described, the internal energy storage circuitcan also be recharged using regenerative braking or during a down time with energy from the battery pack. In some embodiments, the second battery packcan also be used to recharge the internal energy storage circuit.

9 FIG. 992 100 200 980 990 994 992 200 990 994 992 990 994 990 994 200 280 992 shows a seventh application of an internal energy storage circuit. In the embodiment shown, the power toolis a multi-pack power tool, and the controlleris configured to balance a load demand (e.g., a current draw from motor) between the battery packs,using internal energy storage circuit. The controllermay be configured to balance demand placed on the battery packs,according to their capabilities (e.g. balancing different capacity, charge, voltage, ability to provide current, age, temperature, and condition) by charging the internal energy storage circuitusing only one of the battery packs,at a time, based on the to the respective maximum capabilities of the battery packs,. The controllerthen drives the motorusing power drawn from the internal energy storage circuit.

10 10 FIGS.A andB 10 FIG.A 10 FIG.B 1092 1092 200 1080 100 1092 200 250 270 272 274 1090 1080 1090 280 200 1090 1080 1092 280 200 250 270 272 274 1093 1080 1093 280 200 1093 1080 1092 1080 1092 show eighth and ninth applications of the internal energy storage circuitsA andB, respectively. In the embodiment shown in, the controllerdrives the motorA of the power toolusing only power drawn from the internal energy storage circuitA. The controlleris configured to sense (e.g., via sensors,,,) that a condition of the battery packA renders it unable to or unfit to provide sufficient power to the motorA (e.g. due to high-temperature, over-voltage, over-current, cell damage, etc.). In response to determining that the battery packA is unable or unfit to provide power to the motor, the controllerstops drawing power from the battery packA to power the motorA, and draws power from the internal energy storage circuitA to drive the motorinstead. In the embodiment shown in, the controlleris configured to sense (e.g., via sensors,,,) that a condition of a main power supplyB renders it unable to or unfit to provide sufficient power to the motorB (e.g. due to high-temperature, over-voltage, over-current, power outage, etc.). In response to determining that the mains power supplyB is unable or unfit to provide power to the motor, the controllerstops drawing power from the main power supplyB to power the motorB, and instead draws power from the internal energy storage circuitB to drive the motorB. In some embodiments, the internal energy storage circuitB is used to power non-moving components (e.g., emergency egress lighting, lighting around tool stations, or other components), and regenerative braking would be unavailable.

11 FIG. 1192 1190 1190 100 200 1190 1180 1192 100 100 1192 1180 994 100 200 1180 1190 1192 1180 1190 1192 1190 shows a tenth application of an internal energy storage circuit. In the embodiment shown, the voltage of the battery packdecreases in a non-linear manner as the battery packis depleted during operation of the power tool. The controlleris configured to detect when the voltage of the battery packdrops below the predefined threshold and in response enable the motorto draw power from the internal energy storage circuit. This results in a relatively constant operation voltage for the power toolduring a comparatively lengthy operation of the power tool. Using the internal energy storage circuitin this way may also help to stabilize the operation voltage of the motor, resulting in a substantially regular motor speed. In some embodiments where a second battery pack (e.g., battery pack) is connected to the power tool, the controllerconnects the secondary battery pack to the load so that energy from the secondary battery pack drives the motorwhen the voltage of the primary battery packdrops below a predefined threshold. Additionally, energy from the internal energy storage circuitmay be used to drive the motorwhen the voltage of the battery packdrops below the predefined threshold during high-power-demand operations. The internal energy storage circuitcan be charged by the battery pack.

12 FIG. 1292 1280 1290 100 200 250 270 274 1290 1290 200 1292 1280 1292 1290 1290 1290 1290 285 1292 100 200 1292 1280 1290 1192 1190 shows an eleventh application of an internal energy storage circuit. Short momentary spikes in the demand on the motorand battery packduring operations on a varying load may cause the power toolto operate in an inefficient manner. In the embodiment shown, the controllermay be configured to detect (e.g., via sensors,,) a demand (e.g., a voltage demand or a current demand) on the battery packabove a predefined threshold (e.g., a voltage threshold or a current threshold). In response to detecting the increased demand on the battery pack, the controllermay cause the internal energy storage circuitto provide additional power to the motor(e.g., by connecting the internal energy storage circuitin series or parallel with the battery pack) such that the demand on the battery packfalls below the pre-determined threshold. Preventing excess demand on the battery packin this way limits the current through the battery packand the terminals (e.g., in battery pack interface), and therefore limits excess heat generation. This manner of drawing additional power from the internal energy storage circuitmay also help lower performance battery packs complete high-power-demand applications or overcome bind up conditions during operation of the power tool. In the embodiment shown, the controlleris configured to disconnect the internal energy storage circuitfrom the motorwhen the demand on the battery packdrops below the predetermined threshold. The internal energy storage circuitcan be charged by the battery pack.

13 FIG.A 13 FIG.B 13 FIG.A 13 FIG.B 1392 1392 1392 1392 1390 1390 1390 1390 1392 1393 1390 1385 1397 1380 1392 1393 1390 1380 100 1393 1390 1385 1380 andshow different embodiments of the internal energy storage circuitsA andB, respectively. The internal energy storage circuitA,B is a high-voltage capacitor or electrochemical device (e.g., a supercapacitor or a battery) and can operate at a voltage that is higher than the rated voltage of the battery packA,B. This allows the battery packA,B to be configured for virtually any tool or application. In, the internal energy storage circuitB includes an energy storage unitA (e.g., a single capacitor, a single battery cell, etc.) configured to be charged from the battery packA via terminalsA and a boost converterA and to provide power to the motorA. In, the internal energy storage circuitB includes a cluster of energy storage unitsB that are configured to be connected sequentially to a power source (e.g., using switches) in a controlled manner for charging, but may be placed in series or parallel with the battery packB for discharging (e.g., to drive the motorB of the power tool). In some embodiments, the cluster of energy storage unitsB are configured to be charged sequentially from the battery packB via terminalsB and a boost converter and to provide power to the motorB.

292 140 100 292 140 1292 292 200 250 270 272 274 290 292 In some embodiments, the first through eleventh applications of the internal energy storage circuit(described above) may be selected by a user of the power tool via the mode selector. For example, if the user is using the power toolto perform a mixing operation (e.g., starting a concrete mix) having a high-power-demand startup period, the user may select the fifth application of the internal energy storage circuitvia the mode selectorof the power tool. The other applications of the internal energy storage circuitmay also be selected by users for various purposes. In some embodiments, the application of the internal energy storage circuitis automatically selected by the controllerbased on signals from the sensors,,,or the battery pack, and the user does not need to select an application of the internal energy storage circuit.

14 FIG.A 14 FIG.B 14 14 FIGS.A-B 292 292 1405 125 1410 1415 1415 1410 255 280 100 1405 1415 1415 1415 1415 292 105 100 105 andillustrate a circuit schematic of any of the internal energy storage circuits described herein (e.g., internal energy storage circuit) operating in an OFF state and an ON state, respectively. In some embodiments, the internal energy storage circuitincludes a capacitorwhich is selectively connected in series to the battery packand loadvia three switchesA-C. The loadmay include, among other things, the switching network, the motor, and other electrical components of the power tool. In the illustrated embodiment, the capacitoris a low voltage ultra-capacitor (UCAP) capable of being charged to, for example, 14 volts, and the switchesA-C are electronically controllable switches capable of a conducting ON state and a non-conducting OFF state. In other embodiments not detailed herein, other types of capacitors with different device characteristics or other circuit elements, such as high power cells, may be used instead of ultra-capacitors as the internal energy storage circuit. Additionally, various types of switching elements, such as transistors, MOSFETs, BJTs, etc., may be used as the switchesA-C. The internal energy storage circuitshown inmay be incorporated within either the housingof the power toolor external to the housing.

14 14 FIGS.A andB 14 FIG.A 14 FIG.B 292 292 1405 1490 1410 1415 1415 1415 1405 1490 1410 292 1490 1410 1405 1415 1415 1415 1405 1490 1410 292 1405 1490 1410 show an embodiment of the internal energy storage circuitwherein the internal energy storage circuitis a capacitorconfigured to be connected in series with the battery packto power a load. Referring to, when switchA is ON (closed) and switchesB andC are OFF (open), the capacitoris disconnected from the battery packand the load. Thus, the internal energy storage circuitis operating in the OFF state, and the battery packis providing the power to drive the loadwithout supplementary power from the capacitor. Referring to, when switchA is OFF (open) and switchesB andC are ON (closed), the capacitoris connected in series to the battery packand load. Thus, the internal energy storage circuitis operating in the ON state (also referred to as a boost state), and the additional power provided by the capacitorsupplements the power provided by the battery packto drive the load.

15 15 FIGS.A andB 15 FIG.A 15 FIG.B 292 292 1505 1590 1510 1515 1515 1515 1505 1590 1510 292 1590 1510 1505 1515 1515 1515 1505 1590 1510 292 1505 1590 1510 show an embodiment of any of the internal energy storage circuits described herein (e.g., internal energy storage circuit) wherein the internal energy storage circuitis one or more battery cellsconfigured to be connected in series with the battery packto power a load. Referring to, when switchA is ON (closed) and switchesB andC are OFF (open), the one or more battery cellsare disconnected from the battery packand the load. Thus, the internal energy storage circuitis operating in the OFF state, and the battery packis providing the power to drive the loadwithout supplementary power from the one or more battery cells. Referring to, when switchA is OFF (open) and switchesB andC are ON (closed), the one or more battery cellsis connected in series to the battery packand load. Thus, the internal energy storage circuitis operating in the ON state, and the additional power provided by the one or more battery cellssupplements the power provided by the battery packto drive the load.

14 14 15 15 FIGS.A,B,A, andB 1490 1410 1405 1590 1510 1505 In some embodiments, a bypass switch is provided in the circuits shown in, so that the battery packmay be bypassed such that the loadis driven by the capacitoralone, and similarly so that the battery packmay be bypassed such that the loadmay be driven by the one or more battery cellsalone.

292 1490 1590 1410 1510 292 1410 1510 100 292 292 290 1505 1405 100 In some embodiments, by selectively connecting the internal energy storage circuitwith the battery pack,and load,in series, as opposed to in parallel, the internal energy storage circuitis able to provide additional power to drive the load,but may not need transformers for voltage matching or boost converters for voltage step-up. This simplifies the circuitry, increases the efficiency, and decreases the size of the power tool, relative to a parallel-connected internal energy storage circuit. Additionally, the series configuration of the internal energy storage circuitmay allow a higher voltage battery packand the one or more battery cellsor a lower voltage capacitorto be used, thus decreasing the cost of manufacturing the power tool.

16 16 16 FIGS.A,B, andC 16 FIG.A 16 FIG.B 16 FIG.C 292 292 1605 1690 1610 1615 1615 1615 1605 1690 1610 292 1690 1610 1605 1615 1615 1615 1605 1690 1610 292 1605 1690 1610 1615 1615 1615 1605 1610 1690 show an embodiment of any of the internal energy storage circuits described herein (e.g., internal energy storage circuit) wherein the internal energy storage circuitis a capacitorconfigured to be connected in parallel with the battery packto power a load. Referring to, when switchA is ON (closed) and switchesB andC are OFF (open), the capacitoris disconnected from the battery packand the load. Thus, the internal energy storage circuitis operating in the OFF state, and the battery packis providing the power to drive the loadwithout supplementary power from the capacitor. Referring to, when switchA is ON (closed) and switchesB andC are ON (closed), the capacitoris connected in parallel to the battery packand load. Thus, the internal energy storage circuitis operating in the ON state, and the additional power provided by the capacitorsupplements the power provided by the battery packto drive the load. Referring to, when switchA is OFF (open) and switchesB andC are ON (closed), the capacitoralone provides power to drive the load, without any power provided from the battery pack.

17 17 17 FIGS.A,B, andC 17 FIG.A 17 FIG.B 17 FIG.C 292 292 1705 1790 1710 1715 1715 1715 1705 1790 1710 292 1790 1710 1705 1715 1715 1715 1705 1790 1710 292 1705 1790 1710 1715 1715 1715 1705 1710 1790 show an embodiment of any of the internal energy storage circuits described herein (e.g., internal energy storage circuit) wherein the internal energy storage circuitis one or more battery cellsconfigured to be connected in parallel with the battery packto power a load. Referring to, when switchA is ON (closed) and switchesB andC are OFF (open), the one or more battery cellsare disconnected from the battery packand the load. Thus, the internal energy storage circuitis operating in the OFF state, and the battery packis providing the power to drive the loadwithout supplementary power from the one or more battery cells. Referring to, when switchA is ON (closed) and switchesB andC are ON (closed), the one or more battery cellsare connected in parallel to the battery packand load. Thus, the internal energy storage circuitis operating in the ON state, and the additional power provided by the one or more battery cellssupplements the power provided by the battery packto drive the load. Referring to, when switchA is OFF (open) and switchesB andC are ON (closed), the one or more battery cellsalone provide power to drive the load, without any power provided from the battery pack.

292 1690 1790 1610 1710 292 1610 1710 292 1393 100 In some embodiments, by selectively connecting the internal energy storage circuitwith the battery pack,and load,in parallel, as opposed to in series, the internal energy storage circuitis able to provide additional power to drive the load,for a comparatively longer period. Additionally, if the internal energy storage circuitincludes a cluster of units (e.g., cluster of unitsB) the parallel connection allows the malfunction or failure of at least one of the units without causing an interruption in the operation of the power tool.

18 FIG. 1 FIG. 1800 100 1800 100 292 1800 is a flowchart illustrating a control method for providing auxiliary power to a battery pack powered power tool based on operation parameters of the tool. In some embodiments, methodis implemented with one of the embodiments of the power toolofand, accordingly, the methodwill be described with respect to the power tooland a series configuration of the internal energy storage circuit. However, in some embodiments, the methodis implemented with other types of power tools and power source configurations, as described above.

1805 200 212 115 280 200 292 140 In block, the controllerreceives a control signal (e.g., a trigger pull signal) from the user interface(e.g., trigger) indicating a request to drive the motor. The controlleralso receives a selection of a desired application of the internal energy storage circuitvia the mode selector. In some embodiments, the selection of a desired application by a user is optional.

1810 292 200 280 1710 125 292 280 130 200 255 125 280 280 130 200 292 292 125 280 292 280 1415 1415 1515 1515 1615 1615 1715 1715 200 125 280 1415 1515 1615 125 280 In block, in response to the received control signal and selection of the desired application of the internal energy storage circuit, the controllerdrives the motoror load (e.g., load) using a first power source configuration. For example, power from either the battery packor the internal energy storage circuit, or both, are used to drive the motorto drive the output shaft. For example, in response to the received control signal and application selection, the controllermay selectively enable and disable the switching networkto selectively apply power from only the battery packto stator windings of the motor, thus driving the motoror load and the output shaft. In such a case, the controllercontrols the internal energy storage circuitto be disconnected the internal energy storage circuitfrom the battery packand motoror load by controlling internal energy storage circuit inclusion switches that are configured to either include or exclude the internal energy storage circuitfrom supplying power to the motoror load (e.g., switchesB,C,B,C,B,C,B, orC) to be OFF. The controlleralso controls battery pack inclusion switches that are configured to either include or exclude the battery packfrom supplying power to the motoror load (e.g., switchesA,A,A, on 1715A) to be ON to connect the battery packto the motoror load.

1815 280 200 250 270 272 274 250 270 272 274 280 280 200 200 125 292 280 In block, while the motoris being driven, the controllerreceives motor operation data provided from at least one of the sensors,,,. In various embodiments not exhaustively described herein, the sensors,,,may be current sensors that detect a current drawn by the motor, Hall Effect sensors that detect a rotational position, velocity, or acceleration of the motor, or a combination of different types of sensors configured to measure various motor operation characteristics and provide motor operation data indicative of the measured characteristics to the controller. As described above, the controllercan make a determination of if and how to change the configuration of the battery packand the internal energy storage circuitto drive the motoror load.

1820 292 200 292 292 200 1820 200 292 280 1825 200 292 1815 In block, based on the received motor information, or based on the selection of a desired application of the internal energy storage circuit, or both, the controllerdetermines whether to change the power source configuration to, for example, provide additional power from the internal energy storage circuitor to provide power from the internal energy storage circuitonly. For example, in some embodiments, the received motor operation data includes motor current, and the controllercompares the motor current to a current threshold in block. In response to the motor current exceeding the current threshold, the controllermay automatically (without user selection) provide additional power from the internal energy storage circuitto the motorand advances to block. In response to the motor current being below the current threshold, the controllermay automatically determine not to provide additional power from the internal energy storage circuitand returns to block.

1820 200 1815 1820 1820 200 1800 1825 292 125 280 1825 200 292 1415 1415 1415 1515 1515 1515 1615 1615 1615 1415 1715 1715 292 125 280 292 125 280 In block, when the controllerdetermines not to change the power source configuration, blocks-are repeated while the motor continues to be driven. On the other hand, in block, when the controllerdetermines to change the power source configuration, the methodproceeds to blockand, for example, connects the internal energy storage circuitin series with the battery packto provide additional power to the motor. For example, to implement block, the controlleractivates the internal energy storage circuitby controlling the position of switches (e.g., switchesA,B,C,A,B,C,A,B,C,A,B, orC) to connect the internal energy storage circuitto the battery packand load (e.g., motor) in series such that the additional power discharging from the internal energy storage circuitadds to the power provided by the battery packto drive the motor.

292 125 280 292 100 140 292 280 292 100 140 290 285 125 292 280 200 In some embodiments, the internal energy storage circuitis connected in parallel with the battery packto drive the motoror load based on a selection of a desired application of the internal energy storage circuitmade by a user of the power toolvia mode selectorand/or based on motor operation data. In other embodiments, the internal energy storage circuitalone is used to drive the motoror load based on a selection of a desired application of the internal energy storage circuitmade by a user of the power toolvia mode selectorand/or based on motor operation data or based on an indication that the battery packis not connected to the battery pack interface. In some embodiments, the determination of if and how to change the configuration of the battery packand the internal energy storage circuitto drive the motoror load or described herein is made automatically by the controller, without user selection.

Thus, embodiments described herein provide, among other things, an internal energy storage circuit in a battery pack powered power tool that provides auxiliary power to a load of the power tool and a control method of providing said auxiliar power based on motor operational data and/or a user selected internal energy storage circuit application for a battery-powered power tool. Various features and advantages are set forth in the following claims.